Honor views field options

The current version of xspf_playlist_views works against the raw table results, which is not suitable in many cases. Specifically, it doesn't work the way one would expect, mapping title/path info/images/etc.

I'm going to commit a version that uses the proper views field options, while preserving most previous views. However, it's possible, depending on how views were being used previously, that older views may break.

To create a view using the new settings, you'll need to add the desired field labels. That currently means a little manual work, such as 'info' mapping to the node path and 'title' to the node title. However, it does allow for image mappings (the content file/imagefield path to 'image') and emfield youtube videos (the emfield displayed as url to 'location').